The MCAT Bio/Biochem Textbook

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One worked question from each of the 9 categories — a fast check on whether you can spot the concept in a scenario.

Question 1 of 9

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1A — Structure and function of proteins and their constituent amino acids

Question 1

A researcher measures an enzyme's reaction rate across a range of substrate concentrations, with and without compound X. With X present, the measured Vmax is unchanged but the apparent Km increases, and adding a large excess of substrate restores the original rate. Compound X is most likely:

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